In a general packet radio service system (GPRS) network, the system capacity is limited by co-channel interference (CCI) due to frequency reuse. Since the majority of users in a second generation (2G) communication system use voice service, users using packet data service are often limited by Gaussian minimum shift keying (GMSK) interference.
Users of electronic devices require increasing functionality and performance in applications, services and the communication networks used by electronic devices. 2G and second and a half generation (2.5G) networks such as GPRS and EDGE provide high network service coverage and modest bandwidths for many users of electronic devices. In a GPRS network, the system capacity is limited by CCI due to frequency reuse. To further increase spectral efficiency, high-order modulation such as 8 phase shift keying (8 PSK) was adopted in 2G and 2.5G systems in which 3 bits are transmitted in each phase shift. The introduction of high-order modulation increases the complexity of receivers which use maximum likelihood sequence estimation (MLSE). Methods and apparatuses which reduce the complexity of MLSE based receivers for 8 PSK modulation systems may reduce the cost and power consumption of electronic devices while increasing the network performance of the electronic devices.